﻿using System;
using System.Collections.Generic;
using System.IO;
using System.Text.RegularExpressions;
using System.Web;

/// <summary>
/// PathFormater 的摘要说明
/// </summary>
public static class PathFormatter {
	public static string Format(string originFileName, string pathFormat) {
		if (String.IsNullOrEmpty(pathFormat)) {
			pathFormat = "{filename}{rand:6}";
		}

		var invalidPattern = new Regex(@"[\\\/\:\*\?\042\<\>\|]");
		originFileName = invalidPattern.Replace(originFileName, "");

		string extension = Path.GetExtension(originFileName);
		string filename = Path.GetFileNameWithoutExtension(originFileName);

		pathFormat = pathFormat.Replace("{filename}", filename);
		pathFormat = new Regex(@"\{rand(\:?)(\d+)\}", RegexOptions.Compiled).Replace(pathFormat, new MatchEvaluator(delegate(Match match) {
			var digit = 6;
			if (match.Groups.Count > 2) {
				digit = Convert.ToInt32(match.Groups[2].Value);
			}
			var rand = new Random();
			return rand.Next((int)Math.Pow(10, digit), (int)Math.Pow(10, digit + 1)).ToString();
		}));

		pathFormat = pathFormat.Replace("{time}", DateTime.Now.Ticks.ToString());
		pathFormat = pathFormat.Replace("{yyyy}", DateTime.Now.Year.ToString());
		pathFormat = pathFormat.Replace("{yy}", (DateTime.Now.Year % 100).ToString("D2"));
		pathFormat = pathFormat.Replace("{mm}", DateTime.Now.Month.ToString("D2"));
		pathFormat = pathFormat.Replace("{dd}", DateTime.Now.Day.ToString("D2"));
		pathFormat = pathFormat.Replace("{hh}", DateTime.Now.Hour.ToString("D2"));
		pathFormat = pathFormat.Replace("{ii}", DateTime.Now.Minute.ToString("D2"));
		pathFormat = pathFormat.Replace("{ss}", DateTime.Now.Second.ToString("D2"));

		return pathFormat + extension;
	}
}